Check for octals in template spans only, not expressions

test/mjsunit/harmony/templates.js

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Flags: --harmony-templates --harmony-unicode
 
 var num = 5;
 var str = "str";
 function fn() { return "result"; }
 var obj = {
@@ skipping 487 matching lines @@
   }
 })();
 
 
 (function testValidNumericEscapes() {
   assertEquals("8", `\8`);
   assertEquals("9", `\9`);
   assertEquals("\u00008", `\08`);
   assertEquals("\u00009", `\09`);
 })();
+
+
+(function testLegacyOctalEscapesInExpressions() {
+  // Allowed in sloppy expression
+  assertEquals("\x07", `${"\07"}`);
+
+  // Disallowed in template tail
+  assertThrows("`${\"\\07\"}\\07`", SyntaxError);
+
+  // Disallowed in strict expression
+  assertThrows("`${(function() { \"use strict\"; return \"\\07\"; })()}`",
+               SyntaxError);
+})();